.245
a	Vacuum tubes.
h	Book
.100
a	Spangenberg Karl R.
.005
a	00000000000000
.260
a	New York: McGraw-Hill, 1948.
b
c	2000
.084
a	621.319 2 Lep
.300
a	xvii, 860 hlm.
b	gamb., 23 cm. (McGraw-Hill electrical and electronic engineering series)
c	xvii, 860 hlm.; gamb., 23 cm. (McGraw-Hill electrical and electronic engineering series)
.336
a	Book